System and method for determining roadway bank angle

Abstract

A system and method for determining a roadway bank angle based on vehicle information. The method may include the steps of: obtaining vehicle information from at least one vehicle, the vehicle information is obtained from at least one of a global navigational satellite system (GNSS) receiver and one or more onboard vehicle sensors, and the GNSS receiver and the one or more onboard vehicle sensors are installed in the at least one vehicle; performing a roadway bank angle determination process using the obtained vehicle information to obtain a roadway bank angle; and updating a representative roadway bank angle based on the roadway bank angle.

The invention claimed is: 
     
       1. A method of determining a roadway bank angle based on vehicle information, the method comprising the steps of:
 obtaining vehicle information from at least one vehicle, the vehicle information is obtained from at least one of a global navigational satellite system (GNSS) receiver and one or more onboard vehicle sensors, and the GNSS receiver and the one or more onboard vehicle sensors are installed in the at least one vehicle; 
 performing a first roadway bank angle determination process using the obtained vehicle information to obtain a first roadway bank angle, wherein the first roadway bank angle determination process is a vehicle-dynamics-based roadway bank angle determination process; 
 performing a second roadway bank angle determination process using the obtained information to obtain a second roadway bank angle, wherein the second roadway bank angle determination process is an elevation-based roadway bank angle determination process; and 
 updating a representative roadway bank angle based on the first roadway bank angle and the second roadway bank angle. 
 
     
     
       2. The method of  claim 1 , wherein the obtaining vehicle information step includes obtaining onboard vehicle sensor data from the one or more onboard vehicle sensors of the at least one vehicle. 
     
     
       3. The method of  claim 2 , wherein the onboard vehicle sensor data includes suspension sensor data from a plurality of suspension sensors installed on the at least one vehicle. 
     
     
       4. The method of  claim 3 , wherein the vehicle-dynamics-based roadway bank angle determination process includes determining a friction acceleration of the at least one vehicle based on the suspension sensor data. 
     
     
       5. The method of  claim 4 , wherein the vehicle-dynamics-based roadway bank angle determination process includes determining a roll angle of the at least one vehicle. 
     
     
       6. The method of  claim 5 , wherein the roll angle is determined based on the suspension sensor data using a suspension-to-roll angle function. 
     
     
       7. The method of  claim 4 , wherein the vehicle-dynamics-based roadway bank angle determination process includes determining the friction acceleration through use of a roll angle-to-friction acceleration function or a suspension distance-to-friction acceleration function, and determining a lateral acceleration of the at least one vehicle based on the onboard vehicle sensor data. 
     
     
       8. The method of  claim 7 , wherein the following equation is used to determine the roadway bank angle α using the friction acceleration a f , the lateral acceleration a y , gravity g, and roll angle β: 
       
         
           
             
               α 
               = 
               
                 β 
                 - 
                 
                   
                     sin 
                     
                       - 
                       1 
                     
                   
                   ⁢ 
                   
                     
                       
                         
                           a 
                           y 
                         
                         - 
                         
                           
                             a 
                             f 
                           
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           cos 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           β 
                         
                       
                       g 
                     
                     . 
                   
                 
               
             
           
         
       
     
     
       9. The method of  claim 7 , wherein the roll angle-to-friction acceleration function is a modified roll angle-to-friction acceleration function that takes into consideration a weight distribution index and a roadway roughness index. 
     
     
       10. The method of  claim 1 , wherein the vehicle information includes GNSS data that is used to obtain a geographical location of the at least one vehicle, and wherein the GNSS data includes an elevation of the at least one vehicle and is obtained from the GNSS receiver installed in the at least one vehicle. 
     
     
       11. The method of  claim 10 , wherein the elevation-based roadway bank angle determination process includes obtaining roadway map data of an area that contains the geographical location of the at least one vehicle and that includes a portion of a roadway with a roadway curve that is banked. 
     
     
       12. The method of  claim 11 , wherein a curvature extraction process is carried out using the roadway map data to extract roadway curve information concerning the roadway curve, wherein the roadway curve information includes a geographical point representing a center of curvature of the roadway curve. 
     
     
       13. The method of  claim 12 , wherein the elevation-based roadway bank angle determination process includes performing linear regression on a plurality of radial distance-elevation data points derived from a plurality of vehicles travelling along the roadway curve. 
     
     
       14. The method of  claim 13 , wherein a linear regression result is obtained from the linear regression, and wherein the roadway bank angle is determined based on the linear regression result. 
     
     
       15. The method of  claim 12 , wherein the method is carried out at a remote facility that is located remotely from the at least one vehicle, wherein the at least one vehicle includes a first plurality of vehicles and a second plurality of vehicles, wherein the elevation-based roadway bank angle determination process is carried out for the first plurality of vehicles and for the second plurality of vehicles, and wherein the updating step includes aggregating results of the elevation-based roadway bank angle determination processes for the first plurality of vehicles and for the second plurality of vehicles to obtain the representative roadway bank angle. 
     
     
       16. The method of  claim 1 , wherein the at least one vehicle is a plurality of vehicles, wherein the method includes performing a plurality of roadway bank angle processes for the plurality of vehicles, and wherein the updating step includes fusing or otherwise combining results of each of the plurality of roadway bank angle processes to obtain the representative roadway bank angle. 
     
     
       17. A system for determining a roadway bank angle based on vehicle information, the system comprising:
 one or more onboard vehicle sensors; and 
 a processor configured to:
 obtain first vehicle information from the one or more onboard vehicle sensors; 
 obtain second vehicle information from a global navigational satellite system (GNSS) receiver; 
 perform a first roadway bank angle determination process using the first vehicle information to obtain a first roadway bank angle, wherein the first roadway bank angle determination process is a vehicle-dynamics-based roadway bank angle determination process; 
 perform a second roadway bank angle determination process using the second information to obtain a second roadway bank angle, wherein the second roadway bank angle determination process is an elevation-based roadway bank angle determination process; and 
 update a representative roadway bank angle based on the first roadway bank angle and the second roadway bank angle. 
 
 
     
     
       18. The system of  claim 17 , wherein the processor is configured to update the representative roadway bank angle by fusing the first roadway bank angle and the second roadway bank angle.